feat: Add application-level settings for CSS color management

- Introduced a new table `application_setting` to store configurable application options.
- Implemented functions to manage CSS color settings, including loading, updating, and reading environment overrides.
- Added a new settings view to render and manage theme colors.
- Updated UI to include a settings page with theme color management and environment overrides display.
- Enhanced CSS styles for the settings page and sidebar navigation.
- Created unit and end-to-end tests for the new settings functionality and CSS management.

templates/partials/base_header.html

@@ -1,17 +1,3 @@
-{% set nav_links = [
-  ("/", "Dashboard"),
-  ("/ui/scenarios", "Scenarios"),
-  ("/ui/parameters", "Parameters"),
-  ("/ui/currencies", "Currencies"),
-  ("/ui/costs", "Costs"),
-  ("/ui/consumption", "Consumption"),
-  ("/ui/production", "Production"),
-  ("/ui/equipment", "Equipment"),
-  ("/ui/maintenance", "Maintenance"),
-  ("/ui/simulations", "Simulations"),
-  ("/ui/reporting", "Reporting"),
-] %}
-
 <div class="sidebar-inner">
   <div class="sidebar-brand">
     <span class="brand-logo" aria-hidden="true">CM</span>
@@ -20,20 +6,5 @@
       <span class="brand-subtitle">Mining Planner</span>
     </div>
   </div>
-  <nav class="sidebar-nav" aria-label="Primary navigation">
-    {% set current_path = request.url.path if request else "" %}
-    {% for href, label in nav_links %}
-      {% if href == "/" %}
-        {% set is_active = current_path == "/" %}
-      {% else %}
-        {% set is_active = current_path.startswith(href) %}
-      {% endif %}
-      <a
-        href="{{ href }}"
-        class="sidebar-link{% if is_active %} is-active{% endif %}"
-      >
-        {{ label }}
-      </a>
-    {% endfor %}
-  </nav>
+  {% include "partials/sidebar_nav.html" %}
 </div>